Hydrangea plant named ‘H218926’

ABSTRACT

A new and distinct cultivar of  Hydrangea  plant named ‘H218926’, characterized by its upright and uniformly mounded plant habit; vigorous growth habit and rapid growth rate; freely branching habit with strong, thick and sturdy stems; freely and uniformly flowering habit; large mophead-type inflorescences with numerous white and light red purple bi-colored sterile flowers; and good postproduction longevity.

Botanical designation: Hydrangea macrophylla.

Cultivar denomination: ‘H218926’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Hydrangea plant, botanically known as Hydrangea macrophylla, commercially referred to as a mophead-type Hydrangea and hereinafter referred to by the name ‘H218926’.

The new Hydrangea plant is a product of a planned breeding program conducted by the Inventor in De Kwakel, The Netherlands and Lengerich, Germany. The objective of the breeding program was to create new strong and freely-branching Hydrangea plants with strong sturdy stems, uniform flowering habit, large inflorescences with numerous showy sterile flowers, attractive sterile flower color and good postproduction longevity.

The new Hydrangea plant originated from a cross-pollination made by the Inventor in March, 2010 in De Kwakel, The Netherlands, of a proprietary selection of Hydrangea macrophylla identified as code number 07-0132-150, not patented, as the female, or seed, parent with a proprietary selection of Hydrangea macrophylla identified as code number 05-0109-080, not patented, as the male, or pollen, parent. The new Hydrangea plant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated cross-pollination in a controlled greenhouse environment in Lengerich, Germany in March, 2011.

Asexual reproduction of the new Hydrangea plant by vegetative tip cuttings in a controlled environment in De Kwakel, The Netherlands since April, 2011 has shown that the unique features of this new Hydrangea plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Hydrangea have not been observed under all possible combinations of environmental conditions and cultural practices. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘H218926’. These characteristics in combination distinguish ‘H218926’ as a new and distinct Hydrangea plant:

-   -   1. Upright and uniformly mounded plant habit.     -   2. Vigorous growth habit and rapid growth rate.     -   3. Freely branching habit with strong, thick and sturdy stems.     -   4. Freely and uniformly flowering habit.     -   5. Large mophead-type inflorescences with numerous white and         light red purple bi-colored sterile flowers.     -   6. Good postproduction longevity.

Plants of the new Hydrangea can be compared to plants of the female parent selection. Plants of the new Hydrangea differ primarily from plants of the female parent selection in sterile flower color as plants of the new Hydrangea have white and light red purple bi-colored sterile flowers whereas plants of the female parent selection have white-colored sterile flowers.

Plants of the new Hydrangea can be compared to plants of the male parent selection. Plants of the new Hydrangea differ primarily from plants of the male parent selection in sterile flower color as plants of the new Hydrangea have white and light red purple bi-colored sterile flowers whereas plants of the male parent selection have light red purple-colored sterile flowers.

Plants of the new Hydrangea can be compared to plants of the Hydrangea macrophylla ‘H213902’, disclosed in U.S. Plant Pat. No. 26,219. In side-by-side comparisons, plants of the new Hydrangea differ primarily from plants of ‘H213902’ in the following characteristics:

-   -   1. Plants of the new Hydrangea are not as vigorous as plants of         ‘H213902’.     -   2. Plants of the new Hydrangea have larger leaves than plants of         ‘H213902’.     -   3. Plants of the new Hydrangea have smaller panicles than plants         of ‘H213902’.     -   4. Plants of the new Hydrangea have more fertile and sterile         flowers per panicle than plants of ‘H213902’.     -   5. Plants of the new Hydrangea have white and light red purple         bi-colored sterile flowers whereas plants of ‘H213902’ have         white-colored sterile flowers.     -   6. Plants of the new Hydrangea can be successfully “blued” with         aluminum sulfate whereas plants of ‘H213902’ treated with         aluminum sulfate have not been observed to show a discernable         flower color change.

Plants of the new Hydrangea can also be compared to plants of the Hydrangea macrophylla ‘HBA215908’, disclosed in U.S. Plant Pat. No. 29,170. In side-by-side comparisons, plants of the new Hydrangea differ primarily from plants of ‘HBA215908’ in the following characteristics:

-   -   1. Plants of the new Hydrangea have more slender stems than         plants of ‘HBA215908’.     -   2. Plants of the new Hydrangea have smaller panicles than plants         of ‘HBA215908’.     -   3. Sterile flowers of plants of the new Hydrangea are smaller         than sterile flowers of plants of ‘HBA215908’.     -   4. Plants of the new Hydrangea have white and light red purple         bi-colored sterile flowers whereas plants of ‘HBA215908’ have         red purple-colored sterile flowers.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the unique appearance of the new Hydrangea plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photographs may differ from the color values cited in the detailed botanical description which accurately describe the colors of the new Hydrangea plant.

The photograph on the first sheet is a side perspective view of a typical flowering plant of ‘H218926’.

The photograph on the second sheet is a close-up view of a typical inflorescence of ‘H218926’.

The photograph on the third sheet is a side perspective view of a typical flowering plant of ‘H218926’ that has been “blued” (left) that is, treated with aluminum sulfate, and a side perspective view of a typical flowering plant of ‘H218926’ that has not been “blued” (right) that is, not treated with aluminum sulfate.

DETAILED BOTANICAL DESCRIPTION

Plants used in the aforementioned photographs and in the following description were grown during the early spring to summer in 13-cm containers in a glass-covered greenhouse in De Kwakel, The Netherlands and under cultural practices typical of commercial Hydrangea production. During the production of the plants, day and night temperatures averaged 17° C. Plants of the new Hydrangea were ten months old when the photographs and description were taken. Plants of the new Hydrangea can be successfully treated with aluminum sulfate to “blue” the inflorescences. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 2015 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical description: Hydrangea macrophylla ‘H218926’. -   Parentage:     -   -   Female, or seed, parent.—Proprietary selection of Hydrangea             macrophylla identified as code number 07-0132-150, not             patented.         -   Male, or pollen, parent.—Proprietary selection of Hydrangea             macrophylla identified as code number 05-0109-080, not             patented. -   Propagation:     -   -   Type cutting.—By vegetative tip cuttings.         -   Time to initiate roots, summer.—About two weeks at             temperatures about 23° C.         -   Time to initiate roots, winter.—About 18 days at             temperatures about 20° C.         -   Time to produce a rooted young plant, summer.—About four             weeks at temperatures about 23° C.         -   Time to produce a rooted young plant, winter.—About five             weeks at temperatures about 20° C.         -   Root description.—Thick; typically whitish brown in color,             actual color of the roots is dependent on substrate             composition, water quality, fertilizer type and formulation,             substrate temperature and physiological age of roots.         -   Rooting habit.—Freely branching; dense. -   Plant description:     -   -   Plant and growth habit.—Upright and uniformly mounded plant             habit; strong and sturdy stems; rapid growth rate and             vigorous growth habit.         -   Plant height.—About 30 cm to 40 cm.         -   Plant diameter or area of spread.—About 50 cm. -   Lateral branch description:     -   -   Branching habit.—Freely branching habit; when pinched, about             seven to nine lateral branches develop per plant.         -   Length.—About 25 cm to 30 cm.         -   Diameter.—About 6 mm to 8 mm.         -   Internode length.—About 3 cm to 4 cm.         -   Texture.—Smooth, glabrous; fully developed, woody.         -   Aspect.—Upright to about 20° from vertical.         -   Strength.—Strong, sturdy.         -   Color.—When developing: Close to 144C; at internodes, close             to 187C; lenticels, close to 186B. Developed: Close to 144C;             at the internodes, close to 187C; when woody, close to 177C;             lenticels, close to 186B. -   Leaf description:     -   -   Arrangement.—Opposite, simple.         -   Length.—About 12 cm to 15 cm.         -   Width.—About 10 cm to 11 cm.         -   Shape.—Ovate.         -   Apex.—Acute.         -   Base.—Obtuse.         -   Margin.—Dentate.         -   Texture, upper surface.—Smooth to rugose, glabrous.         -   Texture, lower surface.—Rugose, glabrous.         -   Venation pattern.—Pinnate.         -   Color.—Developing leaves, upper surface: Close to 147A.             Developing leaves, lower surface: Close to 147C. Fully             expanded leaves, upper surface: Close to 147A; venation,             close to 146B. Fully expanded leaves, lower surface: Close             to 146B; venation, close to 139D.         -   Petioles.—Length: About 3 cm to 4 cm. Diameter: About 3 mm             to 4 mm. Texture, upper and lower surfaces: Smooth,             glabrous. Color, upper and lower surfaces: Close to 145B. -   Flower description:     -   -   Flower type and habit.—Showy sterile flowers and small             inconspicuous fertile flowers arranged on large mophead-type             terminal panicles; panicles globular in shape; flowers face             upright to outwardly depending on their position in the             inflorescence.         -   Fragrance.—None detected.         -   Natural flowering season.—Plants begin flowering about three             months after planting; flowering begins in the early summer             and is continuous throughout the summer in Northern Europe.         -   Flower longevity.—Fertile flowers last about one month on             the plant, fertile flowers not persistent; sterile flowers             last about four months on the plant, sterile flowers             persistent.         -   Quantity of flowers.—Freely flowering habit; about 40 to 45             fertile flowers per panicle and about 130 to 150 sterile             flowers per panicle.         -   Panicle height.—About 10 cm to 13 cm.         -   Panicle diameter.—About 16 cm to 18 cm.         -   Fertile flower buds.—Length: About 3 mm. Diameter: About             3 mm. Shape: Spherical. Color: Close to 69C.         -   Sterile flower buds.—Length: About 2 mm to 3 mm. Diameter:             About 2 mm. Shape: Spherical. Color: Close to 69C.         -   Fertile flower diameter.—About 3 mm to 4 mm.         -   Fertile flower depth (height).—About 3 mm.         -   Sterile flower diameter.—About 4 cm to 5 cm.         -   Sterile flower depth (height).—About 2 cm.         -   Petals, fertile flowers.—Quantity and arrangement: Five in a             single whorl. Length: About 3 mm. Width: About 2 mm. Shape:             Ovate. Apex: Acute. Base: Attenuate. Margin: Entire.             Texture, upper and lower surfaces: Smooth, glabrous. Color:             When opening, upper and lower surfaces: Close to 145D. Fully             opened, upper surface: Close to N155B with irregular             segments, close to 63C; color does not change with             development. Fully opened, lower surface: Close to 69D;             color does not change with development.         -   Petals, sterile flowers.—Quantity and arrangement: Four in a             single whorl. Length: About 2 mm. Width: About 1.5 mm.             Shape: Ovate. Apex: Acute. Base: Obtuse. Margin: Entire.             Texture, upper and lower surfaces: Smooth, glabrous. Color:             When opening, upper and lower surfaces: Close to 69C. Fully             opened, upper and lower surfaces: Close to 69D; color does             not change with development.         -   Sepals, fertile flowers.—Quantity and arrangement: Five in a             single whorl. Length: About 1 mm to 2 mm. Width: About 1 mm.             Shape: Ovate. Apex: Acute. Base: Obtuse. Margin: Entire.             Texture, upper and lower surfaces: Smooth, glabrous. Color:             When opening, upper and lower surfaces: Close to 145B. Fully             opened, upper and lower surfaces: Close to 145D; color does             not change with development.         -   Sepals, sterile flowers.—Quantity and arrangement: Four in a             single whorl; imbricate. Length: About 2 cm to 2.5 cm.             Width: About 2.2 cm to 2.7 cm. Shape: Deltoid to rhomboidal.             Apex: Obtuse. Base: Cuneate to obtuse. Margin: Entire to             slightly dentate. Texture, upper and lower surfaces: Smooth,             glabrous. Color: When opening, upper surface: Close to 145B             to 145D. When opening, lower surface: Close to 145C. Fully             opened, upper surface: Close to NN155C with random and             irregular sectors, stripes and spots, close to 63C to 63D;             with development, color becoming closer to NN155B with             random and irregular sectors, stripes and spots, close to             63D and 145C; when “blued”, color becoming closer to NN155C             with random and irregular sectors, stripes and spots, close             to 98B to 98C. Fully opened, lower surface: Close to NN155B             with random and irregular sectors, stripes and spots, close             to 63D; color does not change with development.         -   Pedicels, fertile flowers.—Length: About 5 mm to 8 mm.             Diameter: About 1.5 mm to 2 mm. Strength: Strong. Aspect:             Mostly upright. Texture: Smooth, glabrous. Color: Close to             69D.         -   Pedicels, sterile flowers.—Length: About 2 cm to 3 cm.             Diameter: About 2 mm. Strength: Strong. Aspect: Erect to             about 45° from vertical. Texture: Smooth, glabrous. Color:             Close to N155B.         -   Reproductive organs, fertile flowers.—Stamens: Quantity per             flower: Eight. Filament length: About 3 mm. Filament color:             Close to NN155B. Anther length: About 1 mm. Anther shape:             Conical. Anther color: Close to 155B. Pollen amount:             Abundant. Pollen color: Close to 155D. Pistils: Pistil             quantity per flower: Three. Pistil length: About 3 mm to             4 mm. Stigma shape: Oval. Stigma color: Close to NN155B.             Style length: About 1 mm to 2 mm. Style color: Close to             NN155B. Ovary color: Close to NN155B.         -   Reproductive organs, sterile flowers.—Stamens: Quantity per             flower: About six to eight. Filament length: About 3 mm.             Filament color: Close to NN155B. Anther length: About 1 mm.             Anther shape: Conical. Anther color: Close to 155B. Pollen             amount: Moderate. Pollen color: Close to 155B. Pistils:             Pistil quantity per flower: Three. Pistil length: About 3 mm             to 4 mm. Stigma shape: Oval. Stigma color: Close to NN155B.             Style length: About 1 mm to 2 mm. Style color: Close to             NN155B. Ovary color: Close to NN155B.         -   Seeds, only produced by fertile flowers.—Quantity per             fertile flower: About 20 to 30. Length: About 0.5 mm.             Diameter: About 0.1 mm. Color: Close to 200C. -   Pathogen & pest resistance: Under commercial production conditions,     plants of the new Hydrangea have not been observed to be resistant     to pathogens and pests common to Hydrangea plants to date. -   Temperature tolerance: Plants of the new Hydrangea have been shown     to be tolerant to temperatures ranging from about 3° C. to about 38°     C. 

It is claimed:
 1. A new and distinct Hydrangea plant named ‘H218926’ as illustrated and described. 